Upgrade to fluent 0.8.0, fluent-react 0.8.1 (#4935)

* Upgrade to fluent 0.8.0, fluent-react 0.8.1

* Add the attrs prop to Localized where needed

Starting with fluent-react 0.6.0, <Localized> requires the attrs prop to
be passed in order to set any localized attributes as props on the
wrapped component. attrs should be an object with attribute names as
keys and booleans as values. For instance:

    <Localized id="type-name" attrs={{placeholder: true}}>
        <input
            type="text"
            placeholder="Localizable placeholder"
            value={name}
            onChange={…}
        />
    </Localized>

* Use a server-side markup parser

* Use Localized overlay for TimeDiffs

<Localized> can take other React elements as props. If an element of the
same name is then found in the translation, the element passed as prop
is inserted into the translation (keeping its props) and its children
are set to the text content of the element found in the translation.

* Use Localized overlay in AdBanner

locales/en-US/server.ftl

@@ -18,6 +18,7 @@ buttonSignIn =
 screenshotsLogo =
     .title = Screenshots Home
 bannerMessage = Sign in or sign up to access your shots across devices and save your favorites forever.
+bannerUpsell = {gScreenshotsDescription} <a>Get Firefox now</a>
 
 ## Footer
 
@@ -98,6 +99,8 @@ shotPageConfirmDelete = Are you sure you want to delete this shot permanently?
 shotPageShareButton =
     .title = Share
 shotPageCopy = Copy
+shotPageCopyButton =
+    .title = Copy image to clipboard
 shotPageCopied = Copied
 shotPageShareFacebook =
     .title = Share on Facebook
@@ -112,8 +115,8 @@ shotPagePrivacyMessage = Anyone with the link can view this shot.
 shotPageCopyImageText =
     .label = Copy image text
 shotPageConfirmDeletion = Are you sure you want to delete this shot permanently?
-# Note: { $timediff } is a placeholder for a future relative time clause like 'in 3 days' or 'tomorrow'
-shotPageExpirationMessage = If you do nothing, this shot will be permanently deleted { $timediff }.
+# Note: <timediff></timediff> is a placeholder for a future relative time clause like 'in 3 days' or 'tomorrow'
+shotPageTimeExpirationMessage = If you do nothing, this shot will be permanently deleted <timediff></timediff>.
 # Note: { $date } is a placeholder for a localized future date as returned by Date.toLocaleString.
 # For example, in en-US, { $date } could be "7/12/2017, 1:52:50 PM".
 shotPageRestoreButton = restore until { $date }
@@ -140,7 +143,6 @@ shotPageDraw = Draw
 shotPageFavorite = Favorite
 shotPageDelete = Delete
 shotPageScreenshotsDescription = Screenshots made simple. Take, save, and share screenshots without leaving Firefox.
-shotPageUpsellFirefox = Get Firefox now
 shotPageDMCAMessage = This shot is no longer available due to a third party intellectual property claim.
 # Note: { $dmca } is a placeholder for a link to send email (a 'mailto' link)
 shotPageDMCAContact = Please email { $dmca } to request further information.
@@ -164,10 +166,10 @@ shotPageKeepOneMonth = 1 Month
 shotPageSaveExpiration = save
 shotPageCancelExpiration = cancel
 shotPageDoesNotExpire = does not expire
-# Note: { $timediff } is a placeholder for a future relative time clause, like "in 1 week" or "tomorrow"
-shotPageExpiresIn = expires { $timediff }
-# Note: { $timediff } is a placeholder for a past relative time clause, like "1 week ago" or "yesterday"
-shotPageExpired = expired { $timediff }
+# Note: <timediff></timediff> is a placeholder for a future relative time clause, like "in 1 week" or "tomorrow"
+shotPageTimeExpiresIn = expires <timediff></timediff>
+# Note: <timediff></timediff> is a placeholder for a past relative time clause, like "1 week ago" or "yesterday"
+shotPageTimeExpired = expired <timediff></timediff>
 timeDiffJustNow = just now
 timeDiffMinutesAgo = { $number ->
         [one] 1 minute ago
@@ -298,8 +300,6 @@ shotIndexPageSearchResultsTitle = My Shots: search for { $searchTerm }
 shotIndexPageErrorRendering = Error rendering page: { $error }
 shotIndexPageSearchPlaceholder =
     .placeholder = Search my shots
-shotIndexPageSearchButton =
-    .title = Search
 shotIndexPageNoShotsMessage = No saved shots.
 shotIndexPageNoShotsInvitation = Go on, create some.
 shotIndexPageLookingForShots = Looking for your shots…